There is an ever growing interest of telecommunication operators and industry, as well as of service providers, in offering customers of wireless communication networks, such as satellite networks or land mobile networks, the possibility of using their terminals for a variety of applications and in a variety of environments, besides the conventional communication functions.
Some of such new features entail the provision of dedicated peripheral units on the terminal. A widely diffused example is a cellular phone equipped with a digital camera and a removable memory card for storing the pictures shoot by the camera.
Presently, a terminal equipment controls the subscriber identity unit and the peripheral unit (e.g. a memory card) through separate physical and logical channels, and acts on these peripherals as a master in order to perform services which exploit their features separately, i.e. the terminal equipment keeps always the control of the communication.
A mobile phone, for example, exchanges data with the SIM card through a standard interface defined in the 3GPP TS 51.011, while a memory card in the same terminal communicates through its proprietary protocol which depends on the memory card type (i.e. multimedia card, Secure Digital™ card, Memory Stick™).
At present, communication between different components in a mobile terminal, e.g. a subscriber identity unit (the SIM card in 2nd generation mobile terminals or the Universal SIM, U-SIM card in 3rd generation mobile terminals) and a peripheral unit like a memory card is generally not possible, however implementation of such feature would require hardware and/or software modifications in the mobile terminal.
On the other hand it is well known in the art associating SIM cards and memory cards with transceivers for wireless communications, in particular radio communications, for a variety of purposes.
For instance, EP 0 820 178 A discloses a SIM card in which the radio transceiver allows using the terminal for monetary transactions. WO 01/80193 A discloses a SIM card in which the radio transceiver is used for interrogating meters of utility companies. WO 99/59360 A discloses a SIM that can be used by different terminals and that is associated with a wireless communication means for transmitting data, including identity data, to one of such terminals; data transmission can take place in ciphered form. U.S. Pat. No. 6,405,278 B and EP 1 001 358 A disclose flash memories equipped with transceivers for data exchange between the flash memory card and another device.
The Applicant has observed that the prior art documents however only disclose communication of the SIM card or the memory card with external devices, and no suggestion is found about the possibility of setting up a direct communication between the SIM and another peripheral unit without passing through the terminal.
The Applicant has tackled the problem of setting up a secure and terminal-independent communication between a SIM and a peripheral unit such as a memory card. The term SIM, as used herein, includes also the U-SIM and other subscriber identity modules, i.e., modules designed to be used in combination with terminals of a communication network, typically a wireless communication network, to provide at least a user identification and authentication function. For instance, taking into account that the SIM dialogues with the wireless communication network, a terminal-independent communication between the SIM and a peripheral unit could allow the network operator to manage, through the SIM, applications residing on the peripheral unit, without being constrained by the terminal characteristics: an example could be the management of a memory card with ancillary hardware accelerator functions (e.g. for data ciphering) as a data memory or for multimedia functions. The “trusted” characteristics of the SIM would afford the necessary security to the management operations.
In particular, the Applicant has tackled the problem of providing a peripheral unit whose utilization is subject to some check about the subscriber's authorisation, so that for example a memory card can be used for storing sensitive or private data.